補强砂의 强度增加에 관한 硏究

서상열,김준영 영남이공대학 산업기술연구소 1992 産業技術硏究 Vol.6 No.-

To understand the increase effects on the shear strength of reinforced sand an experimental study has been conducted using the modified direct shear box, and a consideration was made on the shear strength tendensy of the reinforced and unreinforced sand, which was obtained through stress-strain relationship. The results of tests were evaluated in terms of the enhancement in shear strength of reinforced sand rather than unreinforced sand. Also shear strength increase effects of reinforced sand were greatest for reinforcement orientation of 30℃with respect to the vertical direction of specimen. It is demonstrated that shear strength increase degreeis considerably altered by tensile specific property of reinfocement.

지반의 동상특성에 관한 실험적 연구(Ⅰ)

徐祥烈 영남이공대학 1998 論文集 Vol.27 No.-

Characteristics of frost heaving were observed for the soil, filled with in the bath which had same soil, initial moisture condition and different cooling temperature. From this study, the following six conclusions were drawn. 1. The frozen depth and the frost heaving pressure increased, but the amount of the frost heave decreased with the low of cooling temperature. 2. The freezing rate varied irregularly depending on voids resulted from development of ice lens and water intake, but it generally decreased with the elapsed time. 3. The amount of frost heave increased with following of a growth of ice ice lens and was almost equal to the total thickness of ice lens. 4. The frost heaving pressure was influenced more strongly by the temperature rather than the pattern of frozen soil. 5. The influence of the external temperature became small with the increase of the frozen depth, temperature variation tended to slow. 6. The thermal movement resulted from the external temperature was mostly shifted towards freezing direction, thermal movement towards horizontal direction compared with freezing direction was very small. The data obtained from this study was based on the phenomenon of frost heave by maintaining a constant temperature. The effect of temperature on frost heave was explained sufficiently by the data, because there was no irregular environmental change as natural phenomenon.

항만공사의 연약지반개량에 관한 연구

徐祥烈 영남이공대학 1997 論文集 Vol.26 No.-

The "4th Development of Seaport on the Pusan" project involved the strengthening of soft soil in a 739,600㎡ site at the Gam-man dong of Pusan. For the design of improvement, conventional bore hole, laboratory tests and piezocones were carried out. This construction site lies over 0.0 to 22.0 m of alluvial and residual soft clay under the reclamated sand fill stratum. The coefficients of consolation obtained in the field measurement and piezocones were greater than the ones obtained in the laboratory tests. The reason for this result seems to be mixing of sand and clay at the top of clay-stratum caused by the reclamation of sand-fill.

동적하중을 받는 PILE의 지반 강성에 관한 연구

서상열 영남이공대학 1992 論文集 Vol.21 No.-

In this paper, new solution analyzing soil stiffness of the pile subjected to dynamic loading is developed by using henkel function. Thus. this solution is comparison with Novak solution. To investigate the effects of soil properties of the disturbed zone around a pile subjected to the torsional harmonic vibration, the parametric study is performed. The determination of the soil stiffness of the soil around a pile is performed by dividing the soil profile into disturbed zone and original zone. The conclusions obtained from this study are as follows: 1) Soil stiffness is greatly affected by the values of soil properties. 2) Real parts of soil stiffness is nearly not affacted by the magnitude of disturbed zone. 3) The real and imaginary parts of the soil stiffness increase as the shear modulus ratio and the poisson's ratio increase.

지반의 동상특성에 관한 실험적 연구(Ⅱ)

서상열 영남이공대학 산업기술연구소 2000 産業技術硏究 Vol.12 No.-

Characteristics of frost heaving were observed for the soil filled with in the natural soil bath. From this study, the following conclusions were drawn. 1. The frozen thickness for soil was thought to be a constant. 2. The amount of ground frost heave increased in line with an increase of the temperature gradient. 3. In cold region, the effect of the tapered pile was low. 4. The amount of ground frost heave coincided with the amount of wate migration at the freezing front. 5. In the case of ice lens near the ground surface, the effect of a sublimation was small. 6. The pressure action on structure was a great difference with the shape of underground object.

하천부지의 효율적 이용방안 : 검단공업단지

徐祥烈 영남이공대학 산업기술연구소 1995 産業技術硏究 Vol.8 No.-

This research is concerned with how seepage through the permeable foundation stratum results upon the safety of embankment constructed on riverbed-the Kumdan industrial complex. The data from the in-situ tests, laboratory tests, and computer program are presented and discussed on the effects of seepage of an alluvial formation. Uplift pressure values were re-presented in the form of pore pressure with the aid of computer program. Emphasis was placed on assessing the influence of seepage under the riverbed embankment. In particular it is shown that: (1) some of levees are constructed on foundation composed of various kinds of alluvial materials underlaid by some form of various kinds of alluvial materials underlaid by some form of bedrock and forms sandwich typed permeable foundation formation that have potential fissuration in case that depth of low permeable upper soil stratum is shallow. (2) this kind of levees as that of the Kumdan industrial complex need to have seepage control methods that are following proposals of reducing quantity, withstanding uplift pressure and lowering piezometric head; ① sheetpile cut-off wall ② compacted barrier of impervious soil ③ grouted or injected cut-off ④ impervious wall of mixed in-place piles.

모래의 비배수 반복비틀림 전단시험에 관한 실험적 연구

成昌煥,徐祥烈 영남이공대학 1997 論文集 Vol.26 No.-

The results obtained from undrained torsional shear test for saturated sand lead to the following conclusions. 1. In the case of monotonic undrained torsional shear test, the more loose sand has, the more maximum excessive pore water pressure happens on a large scale. At that time, large shear strain happens. Also, in the case of one directional monotonic load, there is some possibility for a liquefaction to happen. 2. In undrained cyclic torsional shear test, if strain begins to generate, a loose sand comes to the liquefaction. In a dense sand, the behaviour of a rapid increase of strain is not shown. 3. According to the result compared constant volume test and undrained test, a difference of increased amount of pore water pressure by unloaded process in both tests is a little large. If the liquefaction strength is judged from increase of pore water pressure, loading number in the former is decreased by about 40%.

모래의 투수성에 관한 실험적 연구(Ⅰ)

徐祥烈 영남이공대학 1987 論文集 Vol.16 No.-

Using a newly deviced permeametcr the effect of hydraulic gradient on permeability in sands was investigated, and following observation was made: 1. The flow behavior of water through uniform and graded sand is not linear between velocity and hydraulic gradient except dente sand. 2. T he relationship between permeability k and void ratio e is found to be approximately linear for uniform and graded sand. It is felt that Daroy's Law is not valid for through sand when k is not a constant but is a function of the hydraulic gradient.

粘性土의 透水性에 關한 實驗的 硏究(Ⅰ)

徐祥烈 영남이공대학 1988 論文集 Vol.17 No.-

The relationship between permeability and water content of clayey soil was examined experimentally, and following observation were made: 1. with the increase of initial water content, permeability of clayey soil is decreasing. 2. with the increase of soil pressure, permeability of clayey soil is decreasing. It is considered that the permeability of clayey soil is significantly influenced by initial water content.

Geotextile의 Transmissivity에 瓘한 實驗的 硏究

徐祥烈 영남이공대학 1986 論文集 Vol.15 No.-

Using a newly deviced permeameter the transmissivity of geotextile was evaluated. Major findings of the study were as follows: 1. the flow is significantly influenced by the normal stress applied to the geotextile. 2. transmissivity increases with increasing initial geotextile thickness. 3. transmissivity decreases with increasing normal stress applied to the geatextile. It is felt that the use of bulky geotextile is an effective means of conveying water in construction applications.